Hi @Sergio Londono ,
Thanks for reaching out.
In the Enterprise application, "Enabled for users to sign in?" property to No will not allow any users to sign into your application, even if they're assigned to it. Tokens aren't issued for the application in this scenario.
If you want to restrict users/groups to access your application, then you can use "Assignment required" setting which allow you to further lock down access to the application and let only specified users and applications obtain access tokens.
If this option is set to Yes, then users and other applications or services must first be assigned this application before being able to access it.
Any un-assigned users try to access the application will get below error:
Hope this will help.
Thanks,
Shweta
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